Energy and Emissions Logging in Road Vehicles

Description: Soon, after checking under the hood and kicking the tires, we will be scanning our car's on"board diagnostic system (OBD). Sanjay Sarma has been investigating ways to take advantage of a car's sensor bus, the module that records and conveys information about the vehicle's components and systems. Sarma hopes to make the OBD increasingly useful and essential to consumers concerned about their fuel consumption and carbon footprint.

Car companies have been "cagey" and even "opaque" about the information bus that now comes standard in most cars, but auto enthusiasts have long known how to tap into this system for information on a car's vitals. Sarma, a mechanical engineer comfortable tinkering with car systems, wondered if he could devise a way to gather a continuous stream of data on fuel consumption from OBD, and then come up with accessible and informative metrics for the data. As the internal combustion engine figures less in the future of cars, and batteries and electric motors more, says Sarma, "logging in and learning from this datawill be a bigger and bigger deal."

With a small team of researchers, Sarma conducted hundreds of miles of driving tests in urban and highway settings, micrologging vehicle fuel consumption. They first analyzed the effects of traffic congestion, which demonstrated that traveling slowly did not diminish fuel consumption, because in real life, accelerating and braking frequently wastes energy. They figured out a sampling rate ideal for harvesting an adequate stream of information and avoiding a sea of data, and a way of separating idling time from moving time fuel consumption. Ultimately, Sarma's team came up with "simple kinematic measures" for "flogging" (fuel logging) that could apply to cars of all stripes -- high"performance gas guzzlers, or the latest battery"powered inventions.

Sarma is enthusiastic about the possibility of using cell phones as an interface with a car's OBD. With GPS and accelerometers, cellphones could read out a "weather report of emissions," enabling drivers to determine in real time or historically what segments of a commute consume the most fuel. This information could be shared by other users across the internet. Beyond individual consumer applications, Sarma sees constructive use by public traffic authorities, which could detect fuel consumption/emissions hot spots and speed up long red lights, or even use data in "creative pricing for congestion." Concludes Sarma, "All sorts of things like this are inevitable."

About the Speaker(s): Sanjay Sarma was instrumental in developing the technologies and standards underlying the commmercial RFID industry. He co"founded MIT's Auto"ID Center, and served as its chairman of research. He has taught at MIT since 1996, and received the Cecil and Ida Green Career Development Chair at MIT. He was named a MacVicar Faculty Fellow in 2008.

Sarma has more than 50 publications in computational geometry, virtual reality, manufacturing, CAD, RFID, security and embedded computing. He received the National Science Foundation Career Award, and the New England Business and Technology Award, among others. Sarma is also co"founder of OATSystems, Inc. and serves as its technology advisor.

Sarma received a bachelor's degree from the Indian Institute of Technology in 1989, a master's degree in Mechanical Engineering from Carnegie Mellon University in 1992, and a Ph.D. in Mechanical Engineering from the University of California,Berkeley, in 1995.